Tablet cassette
A tablet cassette in which the tablet is not discharged during an operation to mount and dismount the tablet cassette is provided. In a tablet cassette 1 for containing a number of tablets T, the tablet cassette 1 incorporates a rotor 6 having pocket portions 7 for holding the tablets T. When the tablet cassette 1 is mounted on a mount base 2, rotation of the rotor 6 causes the tablets T held in the pocket portions 7 to be discharged though a discharge port 8. The tablet cassette 1 comprises a press member 16 which is pressed when the tablet cassette 1 is mounted on the mount base 2 and a rotor reversing member 19 for reversing the rotor 6 by a predetermined quantity in conjunction with press of the press member 16.
The present invention relate to a tablet cassette to be mounted on a tablet packing apparatus in which tablets are dispensed and packed in accordance with a prescription of a patient.
BACKGROUND ARTConventionally, in a tablet packing apparatus, a plurality of tablet feeders are provided every kind of tablets. Each tablet feeder comprises a tablet cassette for containing a number of tablets and a mount base on which the tablet cassette is mounted. The tablet cassette has a rotor. The outer surface of the rotor is formed with a plurality of pocket potions each of which comprises a groove extending in an axial direction so as to hold the tablets. On the shaft of the rotor protruding downward from the bottom of the tablet cassette, a rotor gear is attached. On the bottom of the tablets cassette is attached an intermediate gear which engages with the rotor gear. In the rear portion of the bottom of tablet cassette is formed a discharge port which communicates with the pocket portions of the rotor. On the other hand, a motor is incorporated in the mount base. The shaft of the motor protrudes upward. A drive gear is fixed on the upper end of the shaft. When mounting the tablet cassette is mounted on the mount base, the intermediate gear of the tablet cassette engages with the drive gear of the mount base. Driving the motor allows the rotor to rotate via the drive gear, the intermediate gear and the rotor gear. When the pocket portion reaches the discharge port, the tablet held in the pocket portion is discharged thorough the discharge portion and led to a packing unit though a discharge path in the mount base. When the tablet cassette is dismounted from the mount base for replenishment of the tablet or inspection, the intermediate gear of the tablet cassette is disengaged from the drive gear of the mount base, allowing the rotor to freely rotate. Thus, there has been a possibility that the rotor unexpectedly rotates due to impact or vibration to cause the tablet held in the pocket of the rotor to drop from the discharge port into the packing unit, resulting in the tablet packed in a state contaminated by other tablet.
Conventionally, there has been various suggestions for preventing the rotor from unexpectedly rotating when mounting and dismounting the tablet cassette. For example, the patent document 1 discloses a restraint means for engaging with a gear of a rotor due to its elasticity to restrain self-rotation of the rotor when a tablet cassette is dismounted. The patent document 1 also discloses a release means for releasing the engagement of the restraint means with the rotor when the tablet cassette is mounted.
The Patent document 2 filed by the same applicant as the present application discloses: an elastic engagement member that engages with a gear of a rotor to prevent the rotation of the rotor when a tablet cassette is dismounted; and an engagement release member provided on the elastic engagement member that comes into press contact with a proper position of a guide rail of a mount base to release the engagement of the elastic engagement member with the gear when the tablet cassette is mounted.
The patent document 3 discloses an engagement means that directly engaging with and disengaging from a rotor so that the engagement means engages with a peripheral wall of a rotor when a tablet cassette is dismounted and disengaged from the rotor when the cassette is mounted.
Patent document 1: JP 9-30501 A
Patent document 2: JP 9-323702 A
Patent document 3: JP 10-314277 A
DISCLOSURE OF THE INVENTION Problems to be Solved by the InventionHowever, because the systems disclosed in above patent documents prevent rotation of the rotor as the tablet cassette is drawn from or push in the mount base, there is a time point that the rotor can freely rotate during mounting and dismounting operation of the tablet cassette. For a period after starting operation to dismount the tablet cassette form the mount base until, for example, the restraint means of the patent document 1 operates, or a period after releasing the engagement of, for example, the restraint means of the patent document 1 with the rotor during the operation of mounting the tablet cassette on the mount base until the tablet cassette is completely mounted, the rotor can be freely rotated. Thus, there has been a possibility that the rotor is rotated due to impact, causing the tablet held in the pocket portion of the rotor to appear in the discharge port and discharged.
The present invention is made in consideration of above problems. It is an object of the present invention to provide a tablet cassette in which the tablet is not discharged during an operation to mount and dismount the tablet cassette.
MEANS TO SOLVE THE PROBLEMSIn order to solve the above object, the present invention provides a tablet cassette for containing a number of tablets, the tablet cassette incorporating a rotor having pocket portions for holding the tablets, when the tablet cassette is mounted on a mount base, rotation of the rotor causing the tablets held in the pocket portions to be discharged though a discharge port, characterized in that the tablet cassette comprises:
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- a press member which is pressed when the tablet cassette is mounted on the mount base; and
- a rotor reversing member for reversing the rotor by a predetermined quantity in conjunction with press of the press member.
In the above construction of the present invention, when a user presses the press portion in order to mount or dismount the tablet cassette, the rotor reversing member reverses the rotor by a predetermined quantity in conjunction with this press action. Thus, the tablet that has appeared in the discharge port of the tablet cassette returns to inside of the tablet case and disappeared from the discharge port. As a result, when mounting or dismounting operation of the tablet cassette is conducted as the press member is pressed, the tablet is never discharged due to vibration or impact.
Preferably, the press member is a press lever rotatably provided on the tablet cassette. Instead of press lever, press button and so on is available. In a word, a member that is necessarily pressed when a user mounts or dismounts the tablet cassette with respect to the mount base is preferable.
Preferably, the press member comprises a resilient piece extending from the support shaft to the opposite side to the press lever, and the resilient piece comprises an engagement claw for engaging with and disengaging from an engaged portion of a guide rail provided on the mount base. Thus, the engagement claw disengages from the engaged portion of the guide rail when pressing the press member and, in the contrary, the engagement claw engages with the engaged portion of the guide rail when stopping the press member, enabling to mount or dismount the tablet cassette smoothly without causing a vibration and impact.
Preferably, the press member comprises a pair of members which is pressed at the same time when the tablet cassette is held. Thus, it is possible to press the press member with one action only to hold the tablet cassette when mounting and dismounting the tablet cassette.
Preferably, the rotor reversing member is provided on any one of the pair of press member. It is also preferable that the tablet cassette further comprises a biasing member for biasing the press member in a non-pressing direction.
Preferably, the rotor reversing member is an arm extending from the press member, the extremity of the arm is obliquely opposed to teeth of a rotor gear fixed on a shaft of the rotor which protrudes from the bottom of the tablet cassette. The phrase of “the extremity of the arm is obliquely opposed to teeth of a rotor gear” means that the pivot excursion of the extremity of the arm can obliquely intersect with the addendum circle of the rotor gear. In this construction, when the press member is pressed, the extremity of the arm engages with the teeth of the rotor gear to reverse the rotor gear. The reverse amount may be about one pitch of the rotor gear or a length less than the distance between the pocket portions of the rotor.
Preferably, a contact member is provided in the vicinity of the rotor gear so that the distance to the rotor gear can be adjusted, and wherein a portion close to the extremity of the arm comes into contact with the contact member so that the extremity of the arm can enter into a space between the contact member and the rotor gear when the press member is pressed. Thus, with the distance between the contact member and the rotor gear adjusted, the amount that the extremity of the arm enters between the contact surface and the rotor gear when the press member is pressed can be adjusted and also the reverse amount of the rotor gear can be adjusted.
In this case, it is preferable that a flexible portion is provided in at least one part of the arm. As the “flexible portion”, a thin-walled portion formed in a part of the arm, a leaf spring constituting the whole arm or a part of the arm, or a torsion spring attached on the extremity or intermediate of the arm can be adopted. According to this construction, when the extremity of the arm engages with the teeth of the rotor gear, further pivot of the arm causes the flexible portion of the arm to deform. Therefore, even in the case that the reverse amount of the rotor gear, i.e. the movement amount of the arm is reduced, the press portion can be sufficiently pressed, making it easy to operate the press portion.
Preferably, the tablet cassette further comprises a rotation restraint gear which moves in conjunction with press of the press member and engages with the rotor gear to restrain the rotor gear from rotating at a torque less than a predetermined level. According to this construction, when the press member is pressed, the rotation restraint gear moves to engage with the rotor gear. However, if a torque more than a predetermined level is exerted on the rotor gear via the rotor reversing member when pressing the press member, the rotor gear can be reversed. When pressing the press member is stopped and the rotor reversing member returns to an initial position, the torque is less than the predetermined level, preventing the rotor gear once reversed from returning in a forward rotation direction.
Preferably, the rotation restraint gear is movable in a tangent direction of the rotor gear. In this mechanism, when the rotor gear reverses, engagement of the rotor gear with the rotation restraint gear is maintained, while when the rotor gear forwardly rotates, engagement of the rotor gear with the rotation restraint gear is released, allowing the rotation restraint gear to move away from he rotation restraint gear. Thus, even if the rotation restraint gear remains engaged with the rotor gear when pressing the press member is stopped, forward rotation of the rotor when discharging the tablets allows the rotation restraint gear to disengage from the rotor gear. Therefore, a mechanism for disengaging the rotation restraint gear from the rotor gear is not necessary.
EFFECT OF THE INVENTIONAccording to the present invention, as the tablet cassette comprises a press member which is pressed when the tablet cassette is mounted on the mount base and a rotor reversing member for reversing the rotor by a predetermined quantity in conjunction with press of the press member, the tablet that has appeared in the discharge port of the tablet cassette returns to inside of the tablet cassette from the discharge port. As a result, the tablet is never discharged due to vibration or impact, preventing the tablets from admixing.
BRIEF DESCRIPTION OF THE DRAWINGS
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- 1 tablet cassette
- 2 mount base
- 6 rotor
- 7 pocket portion
- 8 discharge port
- 11 rotor gear
- 13 first lever
- 14 second lever
- 16 press lever (Press member)
- 17 resilient piece
- 19 arm (rotor reversing member)
- 20 thin-walled portion (flexible portion)
- 21 engagement claw
- 23 leaf spring (biasing member)
- 31 engaged portion
- 36 rotation restraint gear
Hereinafter, embodiments of the present invention will be described with reference to the accompanied drawings.
First Embodiment
The support portion 4 is formed in a U-shape looking from the bottom of the case 3 as shown in
The first lever 13 and the second lever 14 are biased in a direction that the press portions 18 are separated from each other by a leaf spring 23 made of synthetic resin both ends of which engage with slits 22 formed in the press portions 18 of the press levers 16. On the bottom surface of the tablet cassette 1, as shown in
The mount base 2, as shown in
Operation of the tablet cassette 1 having above construction will be described hereinafter.
The tablet cassette 1 in which tablets T corresponding to the prescription data are contained is driven in accordance with the prescription data. That is to say, the motor 32 of the mount base 2 is driven to rotate the rotor 6 of the tablet cassette 1 so that the tablets T held in the pocket portions 7 are discharged one after another through the discharge port 8 and the tablet guide path 35. A quantity of the discharged tablets T is counted by a sensor not shown provided in the tablet guide path 35. When the quantity of the discharged tablets T reaches a predetermined quantity, the motor 32 is stopped. At this time, an empty pocket portion 7 from which the tablet T is discharged is positioned at the discharged port 8. However, as shown in
When the tablet cassette 1 is mounted, as shown in
The position of the contact member 24 is adjusted in accordance with the size of the tablet T contained in the tablet cassette 1. That is to say, in the case of large tablet T, the adjusting screw 25 of the contact member 24 is loosened to keep the contact member 24 away from the rotor gear 11 as shown in
When the dismounted tablet cassette 1 is put on a shelf or table to release user's hand, the first lever 13 and the second lever 14 pivots due to the biasing force of the leaf spring 23 and returns to the state as shown in
In order to mount the tablet cassette 1 on the mount base 2, in the same manner as when dismounting, the press portions 18 of the first lever 13 and the second lever 14 are pressed against the biasing force with thumb and forefinger or middle finger to hold the tablet cassette 1. This causes the first lever 13 and the second lever 14 to pivot around the support shaft 15 as shown in
Other embodiments will be described hereinafter, though substantially same parts as that of the above first embodiment are given the same numerals to omit the explanation.
Second Embodiment
In the fourth embodiment, operation of the first lever 13 when dismounting and mounting the tablet cassette 1 is same as that of the first embodiment. In the first embodiment, when user's hand is released from the press portion 17 of the press lever 16, the first lever 13 and the second lever 14 pivot due to the biasing force of the leaf spring 23 to return to the initial position shown in
On the other hand, in the fourth embodiment, when the press portion 18 of the second lever 14 as well as the first lever 13 is pressed, the protrusion portion 37 of the second lever 14 presses the rotation restraint gear 36. Thus, the rotation restraint gear 36 moves from the retreat position to the operation position to engage with the rotor gear 11. In this state, the rotor gear 11 never rotates unless a torque more than a predetermined level is exerted. At a torque exerted to the rotor gear 11 when the extremity of the arm 19 of the first lever 13 engages with and presses the teeth of the rotor gear 11, the rotor gear 11 can be rotated. On the other hand, at a torque exerted to the rotor gear 11 when the extremity of the arm 19 of the first lever 13 moves away from the teeth of the rotor gear 11, the rotor gear 11 cannot be rotated. Therefore, there is no possibility that the extremity of the arm 19 forwardly rotates the rotor gear 11 when moving away from the teeth of the rotor gear 11, causing the rotor gear 11 to return to the state before pressing the press lever 16.
When the tablet cassette 1 is dismounted and user's hand is released from the press portion 18 of the first lever 13 and the second lever 14, the protrusion portion 37 of the second lever 14 moves away from the rotation restraint gear 36 while the rotation restraint gear 36 remains engaged with the rotor gear 11. However, if a force having a torque more than a predetermined level exerted on the rotor gear 11 in a direction of forward rotation due to vibration or impact, a turning force transmitted from the teeth of the rotor gear 11 to the teeth of the rotation restraint gear 36 causes the rotation restraint gear 36 to move away from the rotor gear 11 in a tangent direction of the rotor gear 11, i.e. in a direction of arrow as shown in two dots chain line in
Operation of the rotation restraint gear 36 when mounting the tablet cassette 1 on the mount base 2 is same as that when dismounting. So, there is no possibility that the extremity of the arm 19 forwardly rotates the rotor gear 11 when moving away from the teeth of the rotor gear 11, causing the rotor gear 11 to return to the state before pressing the press lever 16. Further, even if user's hand is released from the press portions 18 of the first lever 13 and the second lever 14, the rotation restraint gear 36 remains engaged with the rotor gear 11. However, when the motor 32 is driven in order to discharge the tablet T and a force is exerted on the rotor gear 11 in a direction of forward rotation via the drive gear 34 and the intermediate gear 12, a turning force transmitted from the teeth of the rotor gear 11 to the teeth of the rotation restraint gear 36 causes the rotation restraint gear 36 to move away from the rotor gear 11 in a tangent direction of the rotor gear 11, i.e. in a direction of arrow as shown in two dots chain line in
In the above embodiments, the arm 19 of the press lever 16 of the first lever 13 is formed with the thin-walled portion 20 as a flexible portion integrally with the arm 19, though the arm 19 may be wholly constructed by a leaf spring; the extremity of the arm 19 may be provided with a leaf spring; or the extremity or intermediate of the arm 19 may be attached with a torsion spring.
Claims
1. A tablet cassette for containing a number of tablets, the tablet cassette incorporating a rotor having pocket portions for holding the tablets, when the tablet cassette is mounted on a mount base, rotation of the rotor causing the tablets held in the pocket portions to be discharged though a discharge port, characterized in that the tablet cassette comprises:
- a press member which is pressed when the tablet cassette is mounted on the mount base; and
- a rotor reversing member for reversing the rotor by a predetermined quantity in conjunction with press of the press member.
2. The tablet cassette as in claim 1, wherein the press member is a press lever rotatably provided on the tablet cassette.
3. The tablet cassette as in claim 2, wherein the press member comprises a resilient piece extending from the support shaft to the opposite side to the press lever, and the resilient piece comprises an engagement claw for engaging with and disengaging from an engaged portion of a guide rail provided on the mount base.
4. The tablet cassette as in claim 1, wherein the press member comprises a pair of members which is pressed at the same time when the tablet cassette is held.
5. The tablet cassette as in claim 4, wherein the rotor reversing member is provided on any one of the pair of press member.
6. The tablet cassette as in claim 1, further comprising a biasing member for biasing the press member in a non-pressing direction.
7. The tablet cassette as in claim 1, wherein the rotor reversing member is an arm extending from the press member, the extremity of the arm is obliquely opposed to teeth of a rotor gear fixed on a shaft of the rotor which protrudes from the bottom of the tablet cassette.
8. The tablet cassette as in claim 7, wherein a contact member is provided in the vicinity of the rotor gear so that the distance to the rotor gear can be adjusted, and wherein a portion close to the extremity of the arm comes into contact with the contact member so that the extremity of the arm can enter into a space between the contact member and the rotor gear when the press member is pressed.
9. The tablet cassette as in claim 8, wherein a flexible portion is provided in at least one part of the arm.
10. The tablet cassette as in claim 7, further comprising a rotation restraint gear which moves in conjunction with press of the press member and engages with the rotor gear to restrain the rotor gear from rotating at a torque less than a predetermined level.
11. The tablet cassette as in claim 10, wherein the rotation restraint gear is movable in a tangent direction of the rotor gear.
Type: Application
Filed: Sep 21, 2004
Publication Date: May 24, 2007
Patent Grant number: 7395946
Inventors: Shoji Yuyama (Toyonaka-shi), Shuichi Inoue (Toyonaka-shi), Masaru Kinoshita (Toyonaka-shi)
Application Number: 10/574,075
International Classification: B29C 43/08 (20060101); B28B 5/00 (20060101);